The Labour Leader Ed Miliband has never been renowned for his sense of humour.

Yet his appointment of John Prescott as Labour’s climate change adviser and political campaigner seems like a brilliantly ironic joke. For nothing could be more laughable than the idea that this charmless old bruiser, notorious for his bullying inarticulacy and sleazy infidelity, will enhance Labour’s electoral appeal.

As a lumbering political dinosaur, Prescott is a socialist throwback to the Jurassic age of macho trade union power and untrammelled state control.

His return to front-line politics just shows the depths to which Ed Miliband’s hapless leadership has descended.

This move is an act of comic desperation, not self-confident inspiration. It is a wild, panicky gesture designed to shore up Labour’s traditional heartlands and enthuse the party’s Leftwing activists who still cherish the tribal rhetoric of permanent class war.

Sinking in the opinion polls, Miliband no doubt hopes that Prescott will add some northern proletarian ballast to his own lightweight metropolitan bourgeois vessel.

But the Labour leader is deluded if he thinks such a step will fool the public.

From his epic incompetence to his snarling tribalism, Lord Prescott is a symbol of so much that is wrong with Labour. The man who is now in charge of Labour’s policy on zero carbon emissions has absolutely zero credibility in peddling the green agenda, given that his nickname “Two Jags” stemmed from his fondness for travelling in luxury Jaguars.

During one Labour conference at Bournemouth, he and his wife Pauline infamously used a car to travel just 250 yards. Beyond the partisan ranks of diehard Labour supporters, Prescott has little popularity. He is rightly seen as an old-fashioned machine politician, not a statesman.

When he ran recently for the post of Police Commissioner in Humberside, where he was an MP for 40 years, he came second, well behind the Tory candidate.

Indeed it is amazing that Prescott ever rose so far in British politics. He was neither a gifted administrator nor an effective communicator. His record in office was dismal. He made such a mess of his wide-ranging portfolio as overlord of transport, the environment and the regions from 1997 that eventually most of these responsibilities had to be taken away from him.

His one tangible measure was, typically, a vast extension of unnecessary, expensive state bureaucracy through the creation of a £2billion network of Regional Development Agencies.

His essential mediocrity was reflected in woefulness as a public speaker. On some occasions he was incomprehensible, on others absurd. “The Green Belt is a Labour achievement and we intend to build on it,” was one risible pronouncement.

“It’s great to be back on terracotta,” was another, following a difficult official journey by air.

He is a bad-tempered brute with a thin skin

But there was never anything lovable about these gaffes.

He always came across as a bad-tempered brute with a thin skin and quick fists, as illustrated by the infamous incident in the 2001 General Election when he punched a voter who had thrown an egg at him.

Nor did he ever exude any moral authority, especially not after the revelations of his affair with his Whitehall secretary Tracy Temple.

One former Labour press officer Tricia McDaid described him as “a boastful, arrogant, nasty pig”, adding that “he just jumped on you whenever he felt like it at a party. He had no manners whatsoever.”

This is the figure that Miliband has decided to bring back as an ambassador for his party.

Harriet Harman, the high priestess of socialist feminism and pioneer of Labour’s pink campaign bus, must be thrilled.

The Prescott appointment is another indicator of Labour’s unfitness for office. Instead of recognising its profligate failures in office and embracing new, moderate policies, the party has retreated into its ideological, Left-wing comfort zone.

The return of Prescott, full of class envy, tub-thumping dogma and inverted snobbery, graphically reveals the extent of that retreat. Miliband’s decision can only reinforce the sense that he has pathetically ceded the centreground to the Tory-led Coalition.

That means that he is now losing on every single front. In Scotland, Labour face wipeout from the rampant Scottish Nationalists.

In England, the Green Party’s surge is threatening Labour’s left flank, while the party’s urban heartlands now look increasingly vulnerable to the advance of Ukip.

That sense of drift towards Ukip among the English working class was perfectly encapsulated last week during Miliband’s campaign visit to a British aerospace factory in Lancashire, when electrician Peter Baldwin said that he and his colleagues were “all leaning towards Ukip” because of Labour’s refusal to offer a referendum on EU membership.

“The working-class man in here wants to have a say,” said Mr Baldwin, words that sum up Labour’s alienation from their roots under Miliband’s smug, elitist metropolitan leadership.

Divorced from the political mainstream, devoid of realistic policies, Miliband will only be further undermined by Prescott’s rehabilitation.

Referring to his comeback, Prescott said with egotistical sentimentality that he was “doing it for my grandkids”.

In political terms, the real favour he is doing is for Labour’s opponents.